Fabrication of Gd Ba Cu O films by the metal organic deposition method using trifluoroacetates

We have fabricated Gd–Ba–Cu–O (GdBCO) films on LaAlO 3 single crystalline substrates by a metal–organic deposition method using trifluoroacetates (TFAs). The highest value of the critical temperature of superconductivity ( T c ) of these TFA-derived GdBCO films was 92.9 K and the critical current density ( J c ) reached 2.9 MA cm −2 at 77 K in the self-field. While this value of J c is smaller than that of a previously reported Y–Ba–Cu–O (YBCO) film prepared by the same technique, the critical current density at large magnetic field surpassed that of the YBCO film. The T c of the present GdBCO films depended only weakly on the crystallization temperature and the partial pressure of oxygen ( p O 2 ) for the range of parameters investigated in the present study. On the other hand, J c was found to vary largely with the processing conditions. We discuss the reason for this strong processing parameter dependence of J c by summarizing our results on a p O 2 versus temperature diagram.